Stompbox "on/off" wiring ideas

[Joecool85]

It seems everyone wires their stomp boxes with a stereo jack for the "in" and shorts the ground on the shaft of the incoming plug to turn on the circuit.  Problem is, that means the circuit is "on" and using power even when you aren't using the circuit.  If you use a 3pdt switch, couldn't you keep the ground on/off the same as normal but also wire the positive to switch?  IE - instead of using the 3rd section of the switch to turn the LED on and off, it would turn the whole circuit on and off and the LED would connect straight to the circuit's + and would still only be on "when stomped".  This way the circuit would only draw power when you are plugged in AND stomped so that you are using the circuit.  Now you could leave your pedal plugged in forever without draining the battery, assuming you remember to hit the stomp switch to select pass through mode (which is easy, LED is off = no power being drawn).

The only downside I see is potentially maybe some noise while the circuit powers up when you stomp the switch...but I can't imagine it being much of an issue.  Has anyone tried something like this?

[wormfooduk]

I maybe wrong but wouldn't you get dc on the switch and get really bad poping through the speaker when turn the effect on and off.

[liquids]

I think most people that are power concious use DC jack adaptor power and unplug it, wherever possible.

I've had one pedal that a friend (pre-DIY) modded to switch at the output and switch power via a DPDT switch (no LED) and put a cap across it to minimize the switching pop - this was his idea of true bypass.  So It can be done.  I've re-modded it myself since then....and again, I just unplug my adapter when I want to cut current draw.  I don't mind the minimal trickle most of my pedal draw in current outside of an on LED, when plugged in but not switched on.   Leds seem to be the major current draw in a pedal, and when its switched off, presumably that part of the overall current draw is eliminated.

If you've got a fuzz face and swear by batteries, you could try this - or add a toggle switch so you can 'unplug' the battery manually without having to unplug the jack...plenty of options for how to do it, just depends on what you prefer and dislike for convenience and design.

[merlinb]

I maybe wrong but wouldn't you get dc on the switch and get really bad poping through the speaker when turn the effect on and off.

Yeah, you would get MAJOR popping, plus plenty distortion while the caps all charge up to 4.5V.

[R.G.]

The only downside I see is potentially maybe some noise while the circuit powers up when you stomp the switch...but I can't imagine it being much of an issue.  Has anyone tried something like this?

Yes, tried it. Yes, noise at power up, unless you have done special stuff to avoid the noise. This is possible but potentially as complex as the rest of the circuit put together. And the noise it makes is in general a deafening pop.

It seems everyone wires their stomp boxes with a stereo jack for the "in" and shorts the ground on the shaft of the incoming plug to turn on the circuit.  Problem is, that means the circuit is "on" and using power even when you aren't using the circuit.

Using the input jack as a contact for grounding the power supply is a problem, but for other reasons. This adds the voltage drop of the power through the input wire to the input signal, and can be a source of noise, feedback, and other issues. The only reason this isn't a bigger problem is that the ground wire and contact resistance in pedals is usually low enough to keep it not noticeable.

Historically, the input jack switching was started when only the most advanced professionals had more than one pedal, and when batteries were the only option for powering an effect. Wall warts and quiet 9V adapters had yet to be commonly available. The pedals were not on a pedalboard, but were placed on the floor and connecting cables were re-inserted every time a player set up for a show. Removing the input plug only became a problem with the invention of the pedalboard where the pedals were not re-plugged every time they were used.

This practice will die out as batteries increasingly become useless for pedals, as they are becoming now, with the rise of pedalboards and power adapters. Frankly, I suspect that battery clips in general and the input jack switching circuit will become a thing of the past. Probably the only reason they're still with us is that guitarists worship vintage anything as being worthwhile, and the whole pedal clone industry babbles incessantly about how exactly like the "originals" their products are.

[Mark Hammer]

The why-do-I-always-need-to-leave-the-power-on thread comes up regularly, and meets with the same brick wall simply because that wall is a reality.

I still think someone ought to develop a patch cord that has a little slide switch built into the plug of the "input" side of the cord.  Break the connection between ring and shaft of the input jack, and the battery is disabled without having to unplug anything.

[jefe]

This practice will die out as batteries increasingly become useless for pedals, as they are becoming now, with the rise of pedalboards and power adapters. Frankly, I suspect that battery clips in general and the input jack switching circuit will become a thing of the past. Probably the only reason they're still with us is that guitarists worship vintage anything as being worthwhile, and the whole pedal clone industry babbles incessantly about how exactly like the "originals" their products are.

Since I don't use batteries in my pedals, none of my DIY pedals include a battery clip or stereo input jack. I hate batteries!

[liquids]

Since I don't use batteries in my pedals, none of my DIY pedals include a battery clip or stereo input jack. I hate batteries!

+1 Jefe! ditto.  I use stereo input jack in times when I have multiple boards and/or have lots of things going to ground, for the purpose of star grounding (or almost star grounding) as it adds another close hole to solder into - but I link the ring and sleeve internally in that case (an hence the almost)...

[liquids]

I hate batteries!

And while I'm at it, Jeff, not only do I hate batteries, I also hate your mom, I hate Scott Henderson's hair, I hate the smell of Lady Gaga, and I hate anyone who plays Marshall amps.  Just sayin.'   

[phector2004]

I actually found a nice alternative to jack-powering:

Rotary SPST potentiometers

Currently using one to power-switch a small chip amp I'm working on, but I guess you could use them as volume pots as well? If they offer them in audio taper, that is...

[jefe]

I hate batteries!

And while I'm at it, Jeff, not only do I hate batteries, I also hate your mom, I hate Scott Henderson's hair, I hate the smell of Lady Gaga, and I hate anyone who plays Marshall amps.  Just sayin.'   

Aw... my mom will be heartbroken. 

[Mark Hammer]

And while I'm at it, Jeff, not only do I hate batteries, I also hate your mom, I hate Scott Henderson's hair, I hate the smell of Lady Gaga, and I hate anyone who plays Marshall amps.  Just sayin.'   

Bit of trivia for you.  Did you know that both Scott Henderson's hair AND the smell of Lady Gaga were battery-powered?  So that could account for your antipathy towards all three.  As for Jeff's mom, I am just going to assume that for all she does, like most moms, there is no way on earth she could get that done AND be battery-powered.

Another bit of trivia.  Battery-capable effects are VERY important to showroom sales.  I am quite confident that being able to pop a 9v in the compartment and just take a pedal from the display case and hand it to a prospective buyer to try out (without having to hunt for an adaptor and a nearby available outlet) likely accounts for a good 20%, if not more, of showroom sales.

[jefe]

Another bit of trivia.  Battery-capable effects are VERY important to showroom sales.  I am quite confident that being able to pop a 9v in the compartment and just take a pedal from the display case and hand it to a prospective buyer to try out (without having to hunt for an adaptor and a nearby available outlet) likely accounts for a good 20%, if not more, of showroom sales.

I'm sure you're right about that.

I should add that I've only built pedals for myself, not for sale to others. If I were building a pedal with the intent to sell it, I'd definitely add the battery clip & stereo input jack. Generally speaking, people who buy pedals just expect them to run on 9V batteries.

[Earthscum]

... The pedals were not on a pedalboard, but were placed on the floor and connecting cables were re-inserted every time a player set up for a show. Removing the input plug only became a problem with the invention of the pedalboard where the pedals were not re-plugged every time they were used.

b-b-but... yes, I'm a bassist, but I like my snake of pedals following me to the front of the stage when I run up to rip out a solo with my guitarist! Pedal boards are for weenies who don't know proper application of gaffers tape! It's to keep your cords plugged in!  

Seriously, I get stuck in some weird places on stage where I couldn't possibly get clean enough power to my pedals... I've had to tape patch cords to my drummer's cymbal stand to keep them off the floor and away from the power wires running underneath (stage design seems to be a second thought at most small venues, if they even have a stage). This is why I like batteries, personally... pedal boards are hard to drag around the stage. I like my train of trannies.  

I've been running my Bazz Fuss on the same battery for about 2 years now. My DS-1 only goes through about 1 a year. My phaser would eat about 2 a year before it croaked... now it just drains the battery and doesn't work, lol. My FX-91 has the same battery in it as 3 years ago, and I can't remember if it was new or not... I didn't use it until the last year. My Little Angel, on the other hand, only gets about a dozen 3-4 hour sets out of it.

[R.G.]

Pedal boards are for weenies who don't know proper application of gaffers tape! It's to keep your cords plugged in!  

True. The most general purpose pedalboard is still a roll of duct tape. 

Seriously, I get stuck in some weird places on stage where I couldn't possibly get clean enough power to my pedals...

R.G.'s recipe for Down-Home Battery Power

Ingredients:
Used battery drill from Craigslist with two battery packs; packs preferably 12V rated, but 15V or 18V will work

1. Test the battery packs, preferably before buying. Those things are expensive to buy new!
2. Buy the ... um, donor.
3. Back home, get out the screwdrivers and hacksaw. Take the drill apart, remove the motor from the handle and identify the battery wires coming from the integrated battery socket in the handle.
4. Hacksaw off the drill part, leaving the battery socket intact.
5. Build a 9V regulator into the handle stub.
6. Duct tape... er, affix the handle stub with regulator into your pedalboard neatly.
7. Charge batteries, stick into handle stub on pedalboard, play. Change batteries as needed. Lotsa power available there.

Serves 1, with one backup.

[Scruffie]

Pedal boards are for weenies who don't know proper application of gaffers tape! It's to keep your cords plugged in!  

True. The most general purpose pedalboard is still a roll of duct tape.  

Seriously, I get stuck in some weird places on stage where I couldn't possibly get clean enough power to my pedals...

R.G.'s recipe for Down-Home Battery Power

Ingredients:
Used battery drill from Craigslist with two battery packs; packs preferably 12V rated, but 15V or 18V will work

1. Test the battery packs, preferably before buying. Those things are expensive to buy new!
2. Buy the ... um, donor.
3. Back home, get out the screwdrivers and hacksaw. Take the drill apart, remove the motor from the handle and identify the battery wires coming from the integrated battery socket in the handle.
4. Hacksaw off the drill part, leaving the battery socket intact.
5. Build a 9V regulator into the handle stub.
6. Duct tape... er, affix the handle stub with regulator into your pedalboard neatly.
7. Charge batteries, stick into handle stub on pedalboard, play. Change batteries as needed. Lotsa power available there.

Serves 1, with one backup.

When using Duct tape, I think Steps 3 & 4 there should be replaced with 'Hammer'.

I like the idea though, I have thought of doing an external battery type thing before but couldn't think of a decent source of cheap battery packs.
The one thing I do have from when I was younger are batterys packs for RC Cars, They're just 6 Rechargeable AAs in a pack with a charger connector, I don't have the specs but I did wonder if one of those might be a decent supply for something atleast... maybe a 386 amp.

[Brymus]

If its the ones I used for my RC cars they are 7.2 Volts

[Scruffie]

If its the ones I used for my RC cars they are 7.2 Volts

Pretty sure it was 9.6 or 12V, 12V being more likely at 8 AA Cells.

[Earthscum]

Ya know, the funniest thing about that is that I was actually considering getting a car battery to do just that... yes, a car battery... I'm a smartass, and was joking with a buddy about making a battery powered pedal board that was bigger than his and told him I was gonna use a car battery... then I thought about how funny that would look on stage, and the other bands we play with, and actually started seriously considering it, but I remembered how heavy they are and the idea fizzled. It still amuses me to imagine it, though... like my idea of putting wheelchair wheels on my amp. Amusing, but totally functional.

[Joecool85]

If its the ones I used for my RC cars they are 7.2 Volts

Pretty sure it was 9.6 or 12V, 12V being more likely at 8 AA Cells.

9.6v is 8 AA.  NiCads are only 1.2v each.

Also, it appears that I was right in my second-guessing myself in that there would be all kinds of noise issues if I "turned off" the circuit with the 3pdt.  I'll leave it as is.  I don't hardly go through any batteries, but then again I really don't leave the pedal plugged in unless I'm using it.  I was worried about my brother doing that, he never unplugs his stuff.